Abstract

Rationale
Tobacco smoking is a leading preventable cause of premature morbidity and mortality in people living with severe mental illness. Smoking rates are disproportionately high and abstinence rates low in people with severe mental illness, despite their reported interest in quitting being comparable to that of the general population. Inpatient psychiatry settings have been identified as opportune places to promote and support tobacco cessation amongst people with severe mental illness who smoke, particularly since many hospitals have implemented smoke‐free policies. Evidence is needed to guide policy and practice for tobacco cessation interventions within inpatient psychiatry settings.

Objectives
To assess the effects of smoking cessation interventions on tobacco smoking in adults receiving inpatient psychiatry treatment.

Search methods
We searched the following bibliographical databases and clinical trial registers from inception until 10 February 2026: Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase (Elsevier), PubMed, PsycINFO (EBSCOhost), CINAHL Complete (EBSCOhost), ProQuest Dissertations and Theses Global, ClinicalTrials.gov, World Health Organization International Clinical Trials Registry Platform (WHO ICTRP). We also handsearched the annual meeting abstracts for the Society for Research on Nicotine and Tobacco (SRNT) and screened reference lists of eligible studies.

Eligibility criteria
We included randomised controlled trials (RCTs) and cluster‐RCTs that assessed interventions for tobacco cessation amongst people of 18 years and older who were inpatients in psychiatry settings. Interventions had to be initiated in the psychiatry inpatient setting and aimed at supporting smoking cessation.

Outcomes
Our critical outcome was smoking abstinence at six months (biochemically verified) and our important outcomes included serious adverse events.

Risk of bias
We used the Cochrane risk of bias tool (RoB 2) to assess the outcomes of our review.

Synthesis methods
We synthesised results using meta‐analysis where appropriate, calculating risk ratios using the inverse‐variance random‐effects model. Where this was not possible, we synthesised results following Synthesis Without Meta‐analysis (SWiM) guidelines. We used GRADE to assess our level of certainty in the evidence for our two key outcomes.

Included studies
We included 10 studies that involved 2262 people in total. Three trials were conducted in the USA, two in Australia, two in Taiwan, two in Iran, and one in Israel. The studies took place in emergency or acute and long‐stay psychiatric settings. In most studies, the participants had a mix of diagnoses (e.g. mood disorders, anxiety disorders, schizophrenia), and three studies involved only participants with schizophrenia or schizophrenia‐type disorders.

Five studies tested smoking cessation counselling plus nicotine replacement therapy with post‐discharge follow‐up support versus usual care; one study tested a group behavioural programme for smoking reduction versus waitlist control; and four studies tested pharmacotherapy interventions including smoking medications (bupropion versus placebo, cytisine versus nicotine replacement therapy) and nicotine replacement therapy (different types and doses).

Synthesis of results
We found low‐certainty evidence of increased smoking abstinence from interventions that provided counselling with nicotine replacement therapy and post‐discharge support, compared to usual care, when measured six months after the start of the intervention or hospital discharge (RR 1.81, 95% CI 1.33 to 2.47; P < 0.001, I2 = 0%; 5 studies, 1611 participants; low‐certainty evidence).

Across studies, serious adverse events (SAEs) were low. We pooled four studies reporting deaths at 6 to 18 months after the start of the intervention or hospital discharge. We found that the intervention of smoking cessation counselling plus nicotine replacement therapy with post‐discharge support may result in a slight reduction in deaths compared to usual care, but the results are very uncertain due to low event numbers (22), considerable imprecision, and some concerns about risk of bias (RR 0.81, 95% CI 0.34 to 1.96; P = 0.50, I2 = 0%; 4 studies, 1431 participants; very low certainty evidence).

Authors' conclusions
People receiving inpatient psychiatry treatment may be more likely to have successfully stopped smoking six months after the inpatient intervention when offered smoking cessation counselling plus nicotine replacement therapy with continued post‐discharge support, compared with usual care, but the certainty of the evidence is low.

There was insufficient evidence to determine the effectiveness of other smoking cessation interventions initiated in the psychiatry inpatient setting. More randomised controlled trials, especially those evaluating pharmacological interventions, are needed to strengthen conclusions about treatment effects.

Funding
This Cochrane review had no dedicated funding.

Registration
Protocol (2024) DOI: 10.1002/14651858.CD015934